Abstract:
Examples of the present invention include unreleased coupled multi-cavity resonators and transmission filters. In some examples, the resonators include resonant cavities coupled by acoustic couplers (ABGCs) and acoustic reflectors (ABRs). These acoustic components enable improved confinement of acoustic modes within the resonator to increase the quality factor (Q) and lower the motional resistance (Rx). A coupled resonator with 5 cavities coupled by 4 ABGCs can achieve a Q of 1095 while a single-cavity resonator of the same device size has a Q of 760. In some examples, the devices can be configured to work as electronic transmission filters in at least two types of filter configurations. In the transmission line filter configuration, the device can include a filter structure in an arrangement (LH)N H (LH)N, defined as a Fabry-Perot Resonator (FPR). In the multi-pole filter configuration, the device can include a filter structure in an arrangement similar to the multi-cavity resonator design.